The study investigates the relationship between pre-service teachers' scientific literacy (SL) and their environmental literacy (EL). It also seeks significant differences in SL at different levels of a tendency towards life-long learning (LLT). With the world facing critical environmental problems, an interdisciplinary approach to teaching science and environmental issues may help students to regulate their learning, foster curiosity, and stimulate their motivation to learn, all of which would influence their overall SL. For this pre-service teachers' understanding of SL with respect to the environment is important. The scores from tests that assessed pre-service teachers' SL and EL were analysed for correlation. Findings from the study show that pre-service teachers' SL is correlated with four dimensions of EL, environmental knowledge, environmental attitudes, perception of environmental uses, and environmental concern. Analysis of the data also reveals a significant difference between the SL of participants in the first and third levels of four levels of LLT, while there is no significant difference between the SL of participants at other levels. Implications of the findings are discussed.